Taxi is a language for documenting data models and API contracts, focusing on describing how data and APIs relate across an ecosystem. It uses rich semantic types to map data based on meaning rather than field names, enhancing interoperability and automation in API integration.

Taxi bridges structural and semantic contracts, works with existing schema languages, and supports diverse protocols without requiring significant changes to existing systems. It's designed for readability, expressiveness, and strong typing, facilitating powerful tooling and low-cost changes in data contracts.